A high-resolution climate archive was reconstructed based on carbon isotope analysis and radiocarbon dating of the Chapman baobab in northeastern Botswana. The baobab, which exhibited an open ring-shaped structure composed six stems, collapsed January 2016 during intense El Niño event. Two samples belonging to oldest stems were investigated order obtain a proxy rainfall record, provides insight...

Cancers are the major cause of death worldwide. Chemotherapy using cytotoxic drugs and targeted therapy is required when surgery is difficult, ineffective, or impossible. We previously synthesized the novel synthetic 1-benzylindole derivative 21-900 and found that it inhibits histone deacetylase (HDAC) activities and tubulin assembly. Here we tested its effects on the human leukaemia cell lines...

One of the main barriers blocking sustainable hydrogen production is the use of expensive platinum-based catalysts to produce hydrogen from water. Herein we report the cost-effective synthesis of catalytically active, nitrogen-doped, cobalt-encased carbon nanotubes using inexpensive starting materials-urea and cobalt chloride hexahydrate (CoCl2·6H2O). Moreover, we show that the as-obtained nano...

BACKGROUND A high prevalence of hypogonadism in men with Type-2 diabetes mellitus (T2DM) has been reported worldwide. OBJECTIVES To evaluate the prevalence of hypogonadism in Indian males with T2DM and assess the primary and secondary hypogonadism along with androgen deficiency. MATERIALS AND METHODS In this cross-sectional study, 900 men with T2DM were evaluated using androgen deficiency i...

This paper describes a low-noise, 900-MHz, voltagecontrolled oscillator (VCO) fabricated in a 0.6m CMOS technology. The VCO consists of four-stage fully differential delay cells performing full switching. It utilizes dual-delay path techniques to achieve high oscillation frequency and obtain a wide tuning range. The VCO operates at 750 MHz to 1.2 GHz, and the tuning range is as large as 50%. Th...

The stability condition of a resonator formed by a 900 cone and mirror has been derived using ray tracing techniques. The result showed that this type of resonator is relatively insensitive to mirror misalignment. From this basis, the mirror misalignment tolerance was studied experimentally. Output energy and transverse mode characteristics vs. misalignment were measured, and the results show t...

This paper provides an extension of pathloss analysis in Urban, Rural and Semi-Urban environments in Oman. A new software package has been developed that incorporates modified propagation models and the proposition of radio frequency (RF) network design output for proper and efficient planning to be used by RF engineers for pathloss studies. The root-mean square error (RMSE) was calculated betw...

This study focuses on the leadership structure at the very top of a firm. Specifically, it examines how the presence of a COO/president, who is separate from the CEO, affects strategic change and CEO dismissal. With longitudinal data on the tenures of 207 CEOs, results suggest that the presence of a separate COO/president increases the magnitude of strategic change under conditions of low firm ...